Antibacterial Activity of Silica Nanoparticles Synthesized from Licorice Root Extract against Streptococcus mutans

Silica Nanoparticles Synthesized from Licorice Root Extract as anti Streptococcus mutans

Abstract

One hundred and twenty dental caries samples were collected during the period between September 2023 and January 2024. Streptococcus mutans were isolated and diagnosed based on cultural, microscopic characteristics, and biochemical tests such as IMViC and the Remel RapID STR system. Obtained  results showed that 64 isolates (53.4%) belonged to the genus Streptococci and that 40 isolates (62.5%) of this genus belonged to the species Streptococcus mutans, while 56 isolates (46.6%) of the total 120 isolates did not belong to the genus Non-Streptococci. Silica nanoparticles (SiO2 NPs) was prepared using the aqueous extract of Glycyrrhiza glabra (licorice) root extract and characterized using UV-Visible spectra, X-ray diffraction (XRD), and FESEM. SiO2 NPs showed absorbance peak at 497 nm. The XRD pattern showed that the strong four intense peaks indicate crystalline nature and face centered cubic structure of silica nanoparticles. Field emission scanning electron microscope (FESEM) was used to study the morphology of the SiO2 NPs. It exhibited a spherical shape with diameters of 46 to 77 nm. The obtained results of antibacterial activity showed that the prepared SiO2 NPs were effective against the isolated Streptococcus mutans, as the minimum inhibitory concentration (MIC) value was 12.5 units/mL, and the minimum bactericidal concentration (MBC) value was 25 units/mL.